Specific connectivity optimizes learning in thalamocortical loops.

Thalamocortical loops have a central role in cognition and motor control, but precisely how they contribute to these processes is unclear. Recent studies showing evidence of plasticity in thalamocortical synapses indicate a role for the thalamus in shaping cortical dynamics through learning. Since signals undergo a compression from the cortex to the thalamus, we hypothesized that the computational role of the thalamus depends critically on the structure of corticothalamic connectivity. To test this, we identified the optimal corticothalamic structure that promotes biologically plausible learning in thalamocortical synapses. We found that corticothalamic projections specialized to communicate an efference copy of the cortical output benefit motor control, while communicating the modes of highest variance is optimal for working memory tasks. We analyzed neural recordings from mice performing grasping and delayed discrimination tasks and found corticothalamic communication consistent with these predictions. These results suggest that the thalamus orchestrates cortical dynamics in a functionally precise manner through structured connectivity.

Effectiveness of Electroencephalography Neurofeedback for Improving Working Memory and Episodic Memory in the Elderly: A Meta-Analysis.

Background and Objective: Existing evidence indicates the potential benefits of electroencephalography neurofeedback (NFB) training for cognitive function. This study aims to comprehensively review all available evidence investigating the effectiveness of NFB on working memory (WM) and episodic memory (EM) in the elderly population. Material and Methods: A systematic search was conducted across five databases to identify clinical trials examining the impact of NFB on memory function in healthy elderly individuals or those with mild cognitive impairment (MCI). The co-primary outcomes focused on changes in WM and EM. Data synthesis was performed using a random-effects meta-analysis. Results: Fourteen clinical trials (n = 284) were included in the analysis. The findings revealed that NFB was associated with improved WM (k = 11, reported as Hedges' g = 0.665, 95% confidence [CI] = 0.473 to 0.858, p < 0.001) and EM (k = 12, 0.595, 0.333 to 0.856, p < 0.001) in the elderly, with moderate effect sizes. Subgroup analyses demonstrated that NFB had a positive impact on both WM and EM, not only in the healthy population (WM: k = 7, 0.495, 0.213 to 0.778, p = 0.001; EM: k = 6, 0.729, 0.483 to 0.976, p < 0.001) but also in those with MCI (WM: k = 6, 0.812, 0.549 to 1.074, p < 0.001; EM: k = 6, 0.503, 0.088 to 0.919, p = 0.018). Additionally, sufficient training time (totaling more than 300 min) was associated with a significant improvement in WM (k = 6, 0.743, 0.510 to 0.976, p < 0.001) and EM (k = 7, 0.516, 0.156 to 0.876, p = 0.005); however, such benefits were not observed in groups with inadequate training time. Conclusions: The results suggest that NFB is associated with enhancement of both WM and EM in both healthy and MCI elderly individuals, particularly when adequate training time (exceeding 300 min) is provided. These findings underscore the potential of NFB in dementia prevention or rehabilitation.

The effect of different types of cognitive tasks on postural sway fluctuations in older and younger adults: A nonlinear study.

BACKGROUND: There are numerous types of cognitive tasks classified as mental tracking (MT), working memory (WM), reaction time (RT), discrimination and decision-making and verbal fluency (VF). However, limited studies have investigated the effects of cognitive task type on postural control in older adults. PURPOSE: s: The aim of this study was to investigate the effect of aging and several types of cognitive tasks on postural control in terms of nonlinear analysis. METHOD: Postural control was investigated under 6 conditions (single task and dual-task with RT; easy and difficult VF; easy and difficult WM; easy and difficult MT. Outcome measurements were the max Lyapunov, entropy, and correlation dimension at anteroposterior (AP) and mediolateral (ML) directions. RESULTS: The results revealed that within the older group, the AP & ML max Lyapunov at dual-task with difficult WM and MT was significantly higher than all other conditions. In addition, the older group had lower AP entropy at dual-task with easy VF, difficult WM, and easy as well as difficult MT. CONCLUSION: The results can be useful to understand the postural control mechanisms and to detect the alterations following aging and applying different types of cognitive tasks. In addition, the investigated parameters can be a basis for identifying postural control deficiencies.

A Blended Vitamin Supplement Improves Spatial Cognitive and Short-Term Memory in Aged Mice.

Although many types of antioxidant supplements are available, the effect is greater if multiple types are taken simultaneously rather than one type. However, it is difficult to know which type and how much to take, as it is possible to take too many of some vitamins. As it is difficult for general consumers to make this choice, it is important to provide information based on scientific evidence. This study investigated the various effects of continuous administration of a blended supplement to aging mice. In 18-month-old C57BL/6 mice given a blended supplement ad libitum for 1 month, spatial cognition and short-term memory in the Morris water maze and Y-maze improved compared with the normal aged mice (spontaneous alternative ratio, normal aged mice, 49.5%, supplement-treated mice, 68.67%, p < 0.01). No significant differences in brain levels of secreted neurotrophic factors, such as nerve growth factor and brain-derived neurotrophic factor, were observed between these two groups. In treadmill durability tests before and after administration, the rate of increase in running distance after administration was significantly higher than that of the untreated group (increase rate, normal aged mice, 91.17%, supplement-treated aged mice, 111.4%, p < 0.04). However, training had no reinforcing effect, and post-mortem serum tests showed a significant decrease in aspartate aminotransferase, alanine aminotransferase, and total cholesterol values. These results suggest continuous intake of a blended supplement may improve cognitive function and suppress age-related muscle decline.

A brief real-time fNIRS-informed neurofeedback training of the prefrontal cortex changes brain activity and connectivity during subsequent working memory challenge.

Working memory (WM) represents a building-block of higher cognitive functions and a wide range of mental disorders are associated with WM impairments. Initial studies have shown that several sessions of functional near-infrared spectroscopy (fNIRS) informed real-time neurofeedback (NF) allow healthy individuals to volitionally increase activity in the dorsolateral prefrontal cortex (DLPFC), a region critically involved in WM. For the translation to therapeutic or neuroenhancement applications, however, it is critical to assess whether fNIRS-NF success transfers into neural and behavioral WM enhancement in the absence of feedback. We therefore combined single-session fNIRS-NF of the left DLPFC with a randomized sham-controlled design (N = 62 participants) and a subsequent WM challenge with concomitant functional MRI. Over four runs of fNIRS-NF, the left DLPFC NF training group demonstrated enhanced neural activity in this region, reflecting successful acquisition of neural self-regulation. During the subsequent WM challenge, we observed no evidence for performance differences between the training and the sham group. Importantly, however, examination of the fMRI data revealed that - compared to the sham group - the training group exhibited significantly increased regional activity in the bilateral DLPFC and decreased left DLPFC - left anterior insula functional connectivity during the WM challenge. Exploratory analyses revealed a negative association between DLPFC activity and WM reaction times in the NF group. Together, these findings indicate that healthy individuals can learn to volitionally increase left DLPFC activity in a single training session and that the training success translates into WM-related neural activation and connectivity changes in the absence of feedback. This renders fNIRS-NF as a promising and scalable WM intervention approach that could be applied to various mental disorders.

Association between visuo-spatial working memory and gait motor imagery.

Although motor imagery and working memory (WM) appear to be closely linked, no previous studies have demonstrated direct evidence for the relationship between motor imagery and WM abilities. This study investigated the association between WM and gait motor imagery and focused on the individual differences in young adults. This study included 33 participants (mean age: 22.2 ± 0.9 years). We used two methods to measure the ability of different WM domains: verbal and visuo-spatial WM. Gait motor imagery accuracy was assessed via the mental chronometry paradigm. We measured the times participants took to complete an actual and imagined walk along a 5 m walkway, with three different path widths. The linear mixed effects model analysis revealed that visuo-spatial WM ability was a significant predictor of the accuracy of gait motor imagery, but not of verbal WM ability. Specifically, individuals with lower visuo-spatial WM ability demonstrated more inaccuracies in the difficult path-width conditions. However, gait motor imagery was not as accurate as actual walking even in the easiest path width or in participants with high visuo-spatial WM ability. Further, visuo-spatial WM ability was significantly correlated with mental walking but not with actual walking. These results suggest that visuo-spatial WM is related to motor imagery rather than actual movement.

Working memory signals in early visual cortex are present in weak and strong imagers.

It has been suggested that visual images are memorized across brief periods of time by vividly imagining them as if they were still there. In line with this, the contents of both working memory and visual imagery are known to be encoded already in early visual cortex. If these signals in early visual areas were indeed to reflect a combined imagery and memory code, one would predict them to be weaker for individuals with reduced visual imagery vividness. Here, we systematically investigated this question in two groups of participants. Strong and weak imagers were asked to remember images across brief delay periods. We were able to reliably reconstruct the memorized stimuli from early visual cortex during the delay. Importantly, in contrast to the prediction, the quality of reconstruction was equally accurate for both strong and weak imagers. The decodable information also closely reflected behavioral precision in both groups, suggesting it could contribute to behavioral performance, even in the extreme case of completely aphantasic individuals. Our data thus suggest that working memory signals in early visual cortex can be present even in the (near) absence of phenomenal imagery.

Reduced Prefrontal-Thalamic Theta Flow During Working Memory Retrieval in APP/PS1 Mice.

Background: Working memory deficits in Alzheimer's disease (AD) are linked to impairments in the retrieval of stored memory information. However, research on the mechanism of impaired working memory retrieval in Alzheimer's disease is still lacking. Objective: The medial prefrontal cortex (mPFC) and mediodorsal thalamus (MD) are involved in memory retrieval. The purpose of this study is to investigate the functional interactions and information transmission between mPFC and MD in the AD model. Methods: We recorded local field potentials from mPFC and MD while the mice (APP/PS1 transgenic model and control) performed a T-maze spatial working memory task. The temporal dynamics of oscillatory activity and bidirectional information flow between mPFC and MD were assessed during the task phases. Results: We mainly found a significant decrease in theta flow from mPFC to MD in APP/PS1 mice during retrieval. Conclusions: Our results indicate an important role of the mPFC-MD input for retrieval and the disrupted information transfer from mPFC to MD may be the underlying mechanism of working memory deficits in APP/PS1 mice.

Mindfulness induction and executive function after high-intensity interval training with and without mindful recovery intervals.

OBJECTIVES: Determine the effect of incorporating mindfulness-based activities into the recovery intervals of high-intensity interval training (HIIT) on mindfulness induction and subsequent executive function performance. DESIGNS: A within-subject crossover trial. METHODS: Forty adults participated in two experimental conditions, including a 30-min bout of HIIT involving mindfulness recovery intervals (Mindful) and a 30-min bout of HIIT without mindfulness recovery intervals (Non-mindful), on two separate days in counterbalanced order. Before and after each condition, participants completed the flanker task, switch-flanker task, and n-back task to measure inhibitory control, cognitive flexibility, and working memory, respectively. RESULTS: A higher level of mindfulness state was observed following the Mindful condition than the Non-mindful condition. Dispositional mindfulness was positively correlated with the level of the mindful state only during the Mindful condition but not the Non-mindful condition. The switch-flanker response accuracy was improved from the pretest to posttest during the Non-mindful condition but remained unchanged over time during the Mindful condition. Time-related improvements in the flanker and n-back task outcomes were observed for both the Mindful and Non-mindful conditions and did not differ between conditions. CONCLUSION: Although incorporating mindfulness-based activities during the recovery intervals of HIIT successfully led to greater state-related mindfulness, such a heightened mindful state did not correspond with additional modulation in inhibitory control and working memory performance while attenuating HIIT-related positive changes in task performance requiring cognitive flexibility.

Examining the roles of visual imagery and working memory in the retrieval of autobiographical memories using a dual-task paradigm.

The retrieval of autobiographical memories involves the construction of mental representations of past personal events. Many researchers examining the processes underlying memory retrieval argue that visual imagery plays a fundamental role. Other researchers, however, have argued that working memory is an integral component involved in memory retrieval. The goal of this study was to resolve these conflicting arguments by comparing the relative contributions of visual imagery and working memory during the retrieval of autobiographical memories in a dual-task paradigm. While following a moving dot, viewing a dynamic visual noise (DVN), or viewing a blank screen, 95 participants recalled their memories and subsequently rated them on different memory characteristics. The results suggest that inhibiting visual imagery by having participants view DVN merely delayed memory retrieval but did not affect the phenomenological quality of the memories retrieved. Taxations to the working memory by having participants follow a moving dot, on the contrary, resulted in only longer retrieval latencies and no reductions in the specificity, vividness, or the emotional intensity of the memories retrieved. Whereas the role of visual imagery during retrieval is clear, future studies could further examine the role of working memory during retrieval by administering a task that is less difficult or by recruiting a larger sample than this study. The results of this study seem to suggest that both visual imagery and working memory play a role during the retrieval of autobiographical memory, but more research needs to be conducted to determine their exact roles.

Exploring techniques for encoding spoken instructions in working memory: a comparison of verbal rehearsal, motor imagery, self-enactment and action observation.

Encoding and recalling spoken instructions is subject to working memory capacity limits. Previous research suggests action-based encoding facilitates instruction recall, but has not directly compared benefits across different types of action-based techniques. The current study addressed this in two experiments with young adults. In Experiment 1, participants listened to instructional sequences containing four action-object pairs, and encoded these instructions using either a motor imagery or verbal rehearsal technique, followed by recall via oral repetition or enactment. Memory for instructions was better when participants used a motor imagery technique during encoding, and when recalling the instructions by enactment. The advantage of using a motor imagery technique was present in both verbal and enacted recall. In Experiment 2, participants encoded spoken instructions whilst implementing one of four techniques (verbal rehearsal, motor imagery, observation of others' actions or self-enactment), and then recalled the instructions by oral repetition or enactment. For both verbal and enacted recall, memory for instructions was least accurate in the rehearsal condition, while the other encoding conditions did not differ from each other. These novel findings indicate similar benefits of imagining, observation and execution of actions in encoding spoken instructions, and enrich current understanding of action-based benefits in working memory.

Behavioral and Neural Correlates of Visual Working Memory Reveal Metacognitive Aspects of Mental Imagery.

Mental imagery (MI) is the ability to generate visual phenomena in the absence of sensory input. MI is often likened to visual working memory (VWM): the ability to maintain and manipulate visual representations. How MI is recruited during VWM is yet to be established. In a modified orientation change-discrimination task, we examined how behavioral (proportion correct) and neural (contralateral delay activity [CDA]) correlates of precision and capacity map onto subjective ratings of vividness and number of items in MI within a VWM task. During the maintenance period, 17 participants estimated the vividness of their MI or the number of items held in MI while they were instructed to focus on either precision or capacity of their representation and to retain stimuli at varying set sizes (1, 2, and 4). Vividness and number ratings varied over set sizes; however, subjective ratings and behavioral performance correlated only for vividness rating at set size 1. Although CDA responded to set size as was expected, CDA did not reflect subjective reports on high and low vividness and on nondivergent (reported the probed number of items in mind) or divergent (reported number of items diverged from probed) rating trials. Participants were more accurate in low set sizes compared with higher set sizes and in coarse (45°) orientation changes compared with fine (15°) orientation changes. We failed to find evidence for a relationship between the subjective sensory experience of precision and capacity of MI and the precision and capacity of VWM.

Acousto-optic stimuli to promote coherent 40-Hz frequency entrainment effect.

BACKGROUND: Research has shown that a fundamental frequency of 40 Hz in continuous neural oscillation is indicative of normal brain activity; in Alzheimer disease (AD) patients, these oscillations either disappear or are significantly interrupted. Research has also indicated that the degenerative impacts of AD in mice were mitigated by the synchronization of 40-Hz acousto-optic stimulation (AOS). OBJECTIVE: To examine the impact of employing a 40-Hz AOS intervention on the induction of a substantial 40-Hz frequency entrainment and improvement in working memory performance among a sample of young individuals in good health. We conduct an analysis of event-related potentials (ERPs) derived from electroencephalogram (EEG) data following the presentation of AOS. METHODS: We recruited 20 healthy volunteers (median age: 25 years; 8 female subjects). Following the administration of various stimuli, including no stimuli, 40-Hz AOS, pink noise, and 40Hz acoustic stimuli (AS), the participants were required to complete a working memory task. A total of 62 electrodes were used to record EEG data, which was subsequently analyzed to investigate the impact of AOS on the activity of working memory. We also aimed to determine if AOS lead to a more pronounced 40-Hz frequency entrainment. RESULTS: Following the administration of AOS, a notable enhancement in the 40-Hz power of pertinent cerebral areas was observed, accompanied by a substantial improvement in the performance of the subjects on working memory tests subsequent to the stimulation. CONCLUSION: The findings unequivocally establish the efficacy of using AOS to enhance the 40-Hz power and working memory.

ANTECEDENTES: A pesquisa mostrou que uma frequência fundamental de 40 Hz em oscilação neural contínua é indicativa de atividade cerebral normal. Em pacientes com doença de Alzheimer (DA), essas oscilações desaparecem ou são significativamente interrompidas. A pesquisa também indicou que os impactos degenerativos da DA em camundongos foram mitigados pela sincronização da estimulação acústico-óptica (EAO) de 40 Hz. OBJETIVO: Examinar o impacto do emprego de uma intervenção EAO de 40 Hz na indução de um arrastamento substancial de frequência de 40 Hz e na melhoria do desempenho da memória de trabalho entre uma amostra de jovens com boa saúde. Conduzimos uma análise de potenciais relacionados a eventos (PREs) derivados de dados de eletroencefalograma (EEG) após a apresentação de EAO. MéTODOS: Recrutamos 20 voluntários saudáveis (idade média: 25 anos; 8 mulheres). Após a administração de vários estímulos, incluindo nenhum estímulo, EAO de 40 Hz, ruído rosa e estímulos acústicos (EA) de 40 Hz, os participantes foram obrigados a completar uma tarefa de memória de trabalho. Um total de 62 eletrodos foram utilizados para registrar dados de EEG, que foram posteriormente analisados. para investigar o impacto do AOS na atividade da memória de trabalho. Também pretendemos determinar se o AOS leva a um arrastamento de frequência de 40 Hz mais pronunciado. RESULTADOS: Após a administração de AOS, foi observado um aumento notável na potência de 40 Hz de áreas cerebrais pertinentes, acompanhado por uma melhoria substancial no desempenho dos sujeitos em testes de memória de trabalho subsequentes à estimulação.Conclusão Os resultados estabelecem inequivocamente a eficácia do uso do AOS para melhorar a potência de 40 Hz e a memória de trabalho.

The advantage of being a synesthete: The behavioral benefits of ticker-tape synesthesia.

As first described by Francis Galton, some persons perceive vividly and automatically in their mind's eye the written form of words that they are hearing. This phenomenon, labeled ticker-tape synesthesia (TTS), is thought to reflect an abnormally strong influence of speech processing in language areas on to orthographic representations in the visual cortex. Considering the relevance of TTS for the study of reading acquisition, we looked for objective behavioral advantages or impairments in 22 synesthetes, as compared to 22 matched control participants. In three auditory tasks relying on orthographic working memory (letters counting, backward spelling, and letter shape decision), we predicted and observed better performance in synesthetes than in controls. In two visual tasks (lexical decision and letter decision) with a concurrent auditory stimulation, we predicted that synesthetes should suffer from a larger interference by irrelevant speech than controls, but eventually found no difference between the groups. Those results, which we discuss in relation to orthographic processing, mental imagery, and working memory, promote TTS from pure subjectivity to an experimentally measurable phenomenon.

Effects of virtual reality working memory task difficulty on the passive processing of irrelevant auditory stimuli.

The virtual reality (VR) environment is claimed to be highly immersive. Participants may thus be potentially unaware of their real, external world. The present study presented irrelevant auditory stimuli while participants were engaged in an easy or difficult visual working memory (WM) task within the VR environment. The difficult WM task should be immersive and require many cognitive resources, thus few will be available for the processing of task-irrelevant auditory stimuli. Sixteen young adults wore a 3D head-mounted VR device. In the easy WM task, the stimuli were nameable objects. In the difficult WM task, the stimuli were abstract objects that could not be easily named. A novel paradigm using event-related potentials (ERPs) was implemented to examine the feasibility of quantifying the extent of processing of task-irrelevant stimuli occurring outside of the VR environment. Auditory stimuli irrelevant to the WM task were presented concurrently at every 1.5 or 12 s in separate conditions. Performance on the WM task varied with task difficulty, with accuracy significantly lower during the difficult task. The auditory ERPs consisted of N1 and a later P2/P3a deflection which were larger when the auditory stimuli were presented slowly. ERPs were unaffected by task difficulty, but significant correlations were found. N1 and P2/P3a amplitudes were smallest when performance on the Easy WM task was highest. It is possible that even the easy WM task was so immersive and required many processing resources that few were available for the co-processing of the task-irrelevant auditory stimuli.

Emergence of cortical network motifs for short-term memory during learning.

Learning of adaptive behaviors requires the refinement of coordinated activity across multiple brain regions. However, how neural communications develop during learning remains poorly understood. Here, using two-photon calcium imaging, we simultaneously recorded the activity of layer 2/3 excitatory neurons in eight regions of the mouse dorsal cortex during learning of a delayed-response task. Across learning, while global functional connectivity became sparser, there emerged a subnetwork comprising of neurons in the anterior lateral motor cortex (ALM) and posterior parietal cortex (PPC). Neurons in this subnetwork shared a similar choice code during action preparation and formed recurrent functional connectivity across learning. Suppression of PPC activity disrupted choice selectivity in ALM and impaired task performance. Recurrent neural networks reconstructed from ALM activity revealed that PPC-ALM interactions rendered choice-related attractor dynamics more stable. Thus, learning constructs cortical network motifs by recruiting specific inter-areal communication channels to promote efficient and robust sensorimotor transformation.

Successful alpha neurofeedback training enhances working memory updating and event-related potential activity.

Neurofeedback (NF) is a promising method to self-regulate human brain activity for cognition enhancement. Due to the unclear results of alpha NF training on working memory updating as well as the impact of feedback modality on NF learning, this study aimed to understand further the underlying neural mechanism of alpha NF training effects on working memory updating, where the NF learning was also compared between visual and auditory feedback modalities. A total of 30 participants were assigned to Visual NF, Auditory NF, and Control groups. Working memory updating was evaluated by n-back (n =2,3) tasks before and after five alpha upregulation NF sessions. The result showed no significant difference in NF learning performance between the Visual and Auditory groups, indicating that the difference in feedback modality did not affect NF learning. In addition, compared to the control group, the participants who achieved successful NF learning showed a significant increase in n-back behavioral performance and P3a amplitude in 2-back and a significant decrease in P3a latency in 3-back. Our results in n-back further suggested that successful alpha NF training might improve updating performance in terms of the behavioral and related event-related potential (ERP) measures. These findings contribute to the understanding of the effect of alpha training on memory updating and the design of NF experimental protocol in terms of feedback modality selection.

Long Short-Term Memory-Based Multiomics Reveal Lactobacillus casei-Derived Postbiotics Inhibiting Lipids Digestion via Mediating the Upregulation of α-Helices in Lipase.

SCOPE: The antiobesity function of probiotics has been declared, while the application in high-risk patients and coding side effect has focused attention to postbiotics. This investigation profiles the mechanism of postbiotics affecting lipid digestion at molecular level, and establishes a momentous foundation for the clinical application of postbiotics in obesity suppression. METHODS AND RESULTS: An operational framework for butter digestion is constructed to collect the digests in the intestine at 0, 40, 80, and 120 min with various postbiotics supplement. A total of 227 lipids and 414 metabolites are detected by pseudo-targeted lipidomics integrated with the long short-term memory-based metabolomics, and the triacylglycerol (TG, from 134.1 to 184.7 mg kg-1 ) and diacylglycerol (DG, from 4.2 to 8.4 mg kg-1 ) are identified as significantly different lipids with or without postbiotics supplement. A total of eight substances related to the inhibition of gastric lipase and pancreatic lipase are screened through the molecular simulation computation in silicon and enzymatic reaction kinetics, and thus curtailing the bioaccessibility of lipids. CONCLUSIONS: Lactobacillus casei JCM1134-derived postbiotics propel the structure of lipase to aggregate by increasing the α-helix, and thus hampering the digestion of triglycerides through noncompetitive inhibition.

Effects of ortho-eugenol on anxiety, working memory and oxidative stress in mice.

Ortho-eugenol is a synthetic derivative from eugenol, the major compound of clove essential oil, which has demonstrated antidepressant and antinociceptive effects in pioneering studies. Additionally, its effects appear to be dependent on the noradrenergic and dopaminergic systems. Depression and anxiety disorders are known to share a great overlap in their pathophysiology, and many drugs are effective in the treatment of both diseases. Furthermore, high levels of anxiety are related to working memory deficits and increased oxidative stress. Thus, in this study we investigated the effects of acute treatment of ortho-eugenol, at 50, 75 and 100 mg/kg, on anxiety, working memory and oxidative stress in male Swiss mice. Our results show that the 100 mg/kg dose increased the number of head-dips and reduced the latency in the hole-board test. The 50 mg/kg dose reduced malondialdehyde levels in the prefrontal cortex and the number of Y-maze entries compared to the MK-801-induced hyperlocomotion group. All doses reduced nitrite levels in the hippocampus. It was also possible to assess a statistical correlation between the reduction of oxidative stress and hyperlocomotion after the administration of ortho-eugenol. However, acute treatment was not able to prevent working memory deficits. Therefore, the present study shows that ortho-eugenol has an anxiolytic and antioxidant effect, and was able to prevent substance-induced hyperlocomotion. Our results contribute to the elucidation of the pharmacological profile of ortho-eugenol, as well as to direct further studies that seek to investigate its possible clinical applications.

Regulation of brain cognitive states through auditory, gustatory, and olfactory stimulation with wearable monitoring.

Inspired by advances in wearable technologies, we design and perform human-subject experiments. We aim to investigate the effects of applying safe actuation (i.e., auditory, gustatory, and olfactory) for the purpose of regulating cognitive arousal and enhancing the performance states. In two proposed experiments, subjects are asked to perform a working memory experiment called n-back tasks. Next, we incorporate listening to different types of music, drinking coffee, and smelling perfume as safe actuators. We employ signal processing methods to seamlessly infer participants' brain cognitive states. The results demonstrate the effectiveness of the proposed safe actuation in regulating the arousal state and enhancing performance levels. Employing only wearable devices for human monitoring and using safe actuation intervention are the key components of the proposed experiments. Our dataset fills the existing gap of the lack of publicly available datasets for the self-management of internal brain states using wearable devices and safe everyday actuators. This dataset enables further machine learning and system identification investigations to facilitate future smart work environments. This would lead us to the ultimate idea of developing practical automated personalized closed-loop architectures for managing internal brain states and enhancing the quality of life.